1. Field of the Invention
The present invention relates to a time management system for a memory device processing time-series data, such as animated images and sound data.
2. Description of the Related Art
Recently, computer systems have become multimedia (for example, handling text data, still image data, animated image data, sound data, and the like). Accordingly, it is required that an operating system in such a computer system support multimedia functions.
To cope with these requirements, operating systems having a "multithread" function are advantageous for controlling synchronization between different media. When this operating system processes the time-series data of, for example, animated image data, sound data, etc., the operation system handles the time-series data in such a way that either all of huge amount of time-series data is stored in a real memory of the computer system, or data which are intentionally separated by the operating system is stored in the real memory.
In general, when processing time-series data, it is not necessary to have immediate access to all of the time-series data, it is sufficient to have some of the time-series data for a predetermined time and some time before/after the predetermined time. Accordingly, it is sufficient to store only the required time-series data into the real memory. That is, it is not necessary to provide old data previously used, i.e., from a past time. Therefore, to effectively utilize a data area on the real memory, it is necessary to effectively manage, on a timewise basis, the data area of the real memory.